import json

print('start')


class Person:
    x = 0
    y = 0
    z = 0

    def __init__(self, name, sex='man', age=18):
        self.name = name
        self.sex = sex
        self.age = age


person = Person('tom', age=28)
person.tt = 'TT'

print(str(person))
print(person.x)

person_dict = person.__dict__
print(person_dict)
persionStr = json.dumps(person_dict)
print(persionStr)
